Camp Concentration has 177 pages.
Camp X - novel - has 233 pages.
Joris of the Rock has 325 pages.
Dragon's Rock has 160 pages.
Angel Rock has 320 pages.
The Rock of Tanios has 277 pages.
Shadows on the Rock has 229 pages.
Riven Rock has 496 pages.
The Rock Jockeys has 80 pages.
Amazon shows, "The Camp of the Dog", by Algernon Blackwood listed as having 76 pages.
The Best of L. Sprague de Camp has 301 pages.
The Ghost at Skeleton Rock has 192 pages.